path: root/include/linux/irqnr.h
diff options
authorYinghai Lu <yinghai@kernel.org>2008-12-05 18:58:31 -0800
committerIngo Molnar <mingo@elte.hu>2008-12-08 14:31:51 +0100
commit0b8f1efad30bd58f89961b82dfe68b9edf8fd2ac (patch)
tree239251bad791fd60af8c0f2ba365b7188395c83f /include/linux/irqnr.h
parent218d11a8b071b23b76c484fd5f72a4fe3306801e (diff)
sparse irq_desc[] array: core kernel and x86 changes
Impact: new feature Problem on distro kernels: irq_desc[NR_IRQS] takes megabytes of RAM with NR_CPUS set to large values. The goal is to be able to scale up to much larger NR_IRQS value without impacting the (important) common case. To solve this, we generalize irq_desc[NR_IRQS] to an (optional) array of irq_desc pointers. When CONFIG_SPARSE_IRQ=y is used, we use kzalloc_node to get irq_desc, this also makes the IRQ descriptors NUMA-local (to the site that calls request_irq()). This gets rid of the irq_cfg[] static array on x86 as well: irq_cfg now uses desc->chip_data for x86 to store irq_cfg. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'include/linux/irqnr.h')
1 files changed, 3 insertions, 11 deletions
diff --git a/include/linux/irqnr.h b/include/linux/irqnr.h
index 452c280c811..7a299e989f8 100644
--- a/include/linux/irqnr.h
+++ b/include/linux/irqnr.h
@@ -7,18 +7,10 @@
# define for_each_irq_desc(irq, desc) \
for (irq = 0; irq < nr_irqs; irq++)
-extern int nr_irqs;
-# define for_each_irq_desc(irq, desc) \
- for (irq = 0, desc = irq_desc; irq < nr_irqs; irq++, desc++)
-# define for_each_irq_desc_reverse(irq, desc) \
- for (irq = nr_irqs - 1, desc = irq_desc + (nr_irqs - 1); \
- irq >= 0; irq--, desc--)
+static inline early_sparse_irq_init(void)
-#define for_each_irq_nr(irq) \
- for (irq = 0; irq < nr_irqs; irq++)